Try burning the sugar cube with the lit match first. It shouldn't burn.

Now dip the sugar cube in cigarette ash (carbon) and light it again. It should light
much more easily.

The carbon heats up and raises the temperature of the surrounding sugar crystals to
the ignition temperature required for the sugar to burn. Once these first crystals are
burning, they provide sufficient heat for the neighbouring crystals to continue burning.

Face Paint

Mix cornstarch, water and cold cream together thoroughly. Spoon into containers, one
for each colour. Add food colouring to each container of face paint. Use brushes to paint
faces.

This face paint washes of with soap and water.

How Much Oxygen is in Air

Safety Rules:
Parent supervision
Take care with fire or heat

Materials you need are:
a large clear container
a smaller clear container
water
a small candle
a small light dish on which the candle floats
matches

Set up the materials as in the diagram. Light the candle and put the cover over it
last. Wait a few minutes until the candle goes out. Watch the water in the small container
rise.

Oxygen takes up almost 20% or one-fifth of air. When all of the oxygen in the
container has been used in burning the candle, it will be replaced by the water rising.

Invisible Ink

Safety Rules:
Parent supervision
Take care with fire or heat

Materials you need are:
freshly-squeezed lemon juice
a toothpick or a fine stick as a pen
a sheet of paper
a candle
matches

The 'ink' is the lemon juice. Dip the toothpick or fine stick into the lemon juice and
write your name on the paper. Allow it to dry completely. Light the candle and hold the
paper above the flame so that heat only burns the lemon juice writing but not the paper.

The ignition temperature needed to burn the sugar in the lemon juice is lower than
that of the paper.